Hydraulic gates



April 23, 1963 P. F. DANEL 3,086,366

HYDRAULIC GATES Filed July 8, 1958 4 Sheets-Sheet 1 llfilll INVENTOR PIERRE E DANEL ATTORNEYS- Apnl 23, 1963 P. F. DANEL 3,086,366

HYDRAULIC GATES Filed July 8, 1958 4 Sheets-Sheet 2 DEC/MAL 0F FULL OPENING OF GA TE DISTANCE d DOWNSTREAM FROM GATE TO GROOVES AS DEC/MAL OF FULL GATE OPENING 1: 1-4-0- INVENTOR PIERRE F. DANEL I M W?/W.

ATTORNEYS April 23, 1963 F. DANEL HYDRAULIC GATES Filed July 8, 1958 4 Sheets-Sheet 3 INVNTOR PIERRE E DANEL TQLZZLE ATTORNEYS April 23, 1963 P. F. DANEL HYDRAULIC GATES 4 Sheets-Sheet 4 INVENTOR Filed July 8, 1958 P/ERRE F DANEL A ORNEYS United States Patent 3,086,366 HYDRAULIC GATES Pierre F. Dane], La Tranche, France, assignor to Societe Grcnobloisc dlltudes et lApplications Hydrauliques, Grenoble, France, a corporation of France Filed July it, 1958, Ser. No. 747,222 Claims priority, application France July 11, 1957 19 Claims. (Cl. 61-28) This invention relates to hydraulic gates which conventionally are supported for sliding movement on slideways or for rolling movement of their supporting rollers on rollways parallel to the plane of movement of the gate transversely of the flow for shutting oil and for controlling the flow of hydraulic fluid flowing in a channel or in a hydraulic ilow .tunnel or conduit.

The invention broadly relates to a hydraulic channel and gate construction of this type for controlling water flow in which the channel is defined by a base wall and lateral walls extending generally parallel to the direction of the how, the gate being supported so as to be moved transversely of the iiow to any position between an open position in which the flow controlling edge thereof at the side thereof toward the base wall is spaced from the base wall and a closed position in which the how controlling edge cooperates with the base wall to shut off the flow, the lateral edges of the gate in any position thereof also cooperating to this end with the lateral walls of the channel. In such construction, when the how is generally horizontal, the base wall may be generally horizontal, the lateral walls being disposed generally vertically. The construction may be one in which the channel is open above the lateral walls or one in which opposite to the base wall a top wall cooperates with the lateral walls and the base wall to form a closed conduit which may be under the hydraulic pressure of an upstream head and may constitute a hydraulic flow tunnel.

Within the scope of the invention, however, the channel may be constructed as a closed conduit or tunnel capable of confining the water under pressure with the direc tion of flow inclined to the horizontal at any desired angle, or may be vertical, the base wall and the opposed closing wall and the lateral walls being disposed in corresponding inclined or vertical positions. In the following description the base wall will be understood to be that wall between Which and the flow controlling edge of the gate the opening or orifice is formed through which ilow takes place and the closing wall, which may be a top wall, to be the wall opposite the base wall. For simplicity in explanation the invention will be described in connection with the construction in which the extent of the channel and its base wall is generally horizontal, the lateral walls being disposed vertically and the gate being disposed for vertical movement transversely of the channel toward and away from the base Wall. It will be understood, however, that the conditions about to be described which are utilized and the features of the channel and gate construction of the invention are the same whether the channel is an open channel for generally horizontal flow or a closed conduit capable of confining the water under pressure.

"It is well known that the water flowing through a restricted opening such as is determined by the position of the gate, whether this restriction provides only a relatively small part of the full area of the flow available if the gate were fully open or, on the other hand, provides a large fraction of such full area, becomes contracted in cross sectional area of the stream, usually in its depth, as it flows past the flow controlling edge of the gate. In this contracted region it is found that there is established a vertical gradient of velocity. That is to say, that in any plane transverse to the how the velocity of the water decreases in the direction toward the base wall. There exists a 3,036,356 Patented Apr. 23, 1963 "ice corresponding gradient of static pressure which increases in this direction in this plane. These conditions exist concomitantly with the changes in the direction of the movement of the layers of water which are turned from the direction parallel to the base wall toward the base wall and then are turned about the control edge of the gate and then again to'iiow generally parallel to the base wall downstream of the gate.

At a substantial distance from the gate upstream or downstream where the flow is parallel to the base Wall the velocity is substantially the same at all points in the transverse planc. In these regions there exists only a relatively small gradient of normal static pressure due to the height of the water in the channel if the flow is generally horizontal and the transverse plane vertical. In the contracted region, there is added to the normal gradient of static pressure, an additional gradient of static pressure due to the contraction in the area of flow of the water in said region and having value-s larger than the normal gradient of static pressure. This combination of pressures in the said contracted region result in an excessive gradient of static pressure which is detrimental to the conventional channel and gate constructions as about to be explained.

in hydraulic constructions of the type above referred to it is necessary to provide for support of the slideways or rollways above mentioned at the lateral walls of the tunnel or channel. In order to avoid obstruction to the stream of water in the portions thereof adjacent these lateral walls which would occur if the supporting rollways or slideways were disposed outwardly from the faces of the lateral walls in the stream, these rollways or slideways ordinarily aredisposed in grooves formed inwardly of the faces of the lateral walls so that the water flowing along the faces of the lateral walls beneath the bottom edge of the gate, although it must pass across these grooves, nevertheless has a relatively direct unobstructed path in the portions of the stream adjacent these lateral walls.

It is found, however, that the gradient of pressure above mentioned, which is mostly the result of the velocity distribution in the contracted layers of water moving about the control or bottom edge of the gate which is restricting flow, causes the formation of jets of the water immediately adjacent the lateral walls, that is, some of the water becomes directed transversely of the direction of flow toward the interior surfaces of the grooves, striking these interior walls of the grooves with considerable force when conventionally the gate itself isdisposed adjacent the plane of the grooves. As a result there are developed eddies and cavitation which, as well as the direct action of the jets, cause vibration and wear which are detrimental to proper operation of the hydraulic plant and to the maintenance of the channel and the gate structure in good order.

It is an object of the invention to provide a hydraulic plant utilizing a cut-off gate for controlling the flow of water through a fiow tunnel or channel which will avoid or greatly reduce the efiect of the development of the jets and eddies and cavitation just referred to.

It is another object of the invention to provide a hydraulic plant construction in which the gate supporting means is disposed in a region in which the vertical gradient of pressure in the stream of water due to the contraction provided by the gate is not developed or is substantially dissipated.

It is a further object of the invention to provide a hydraulic gate of unique construction which will elfect the requisite control of the flow and of the movement of the water about its control edge, while being adapted to be supported for its movement transversely of the direction of hydraulic flow by supports disposed in a region of the fiow which is not subjected to the effects of the flow about the gate referred to.

In order to accomplish the purposes of the invention advantage is taken of the conditions which have been observed in hydraulic flow through orifices, such as are formed between the flow control edge of a gate and the base wall of the channel, with respect to the change in the static pressure in the stream of water flowing in the regions of curving flow upstream of the gate and about the control edge of the gate and downstream from the gate. As will be more clearly understood from the description taken in connection with the drawings, the isobars of static pressure in the mass of flowing water may be drawn, for example, on a vertical longitudinal section of the stream for the different regions of the flow from points upstream of the gate to points downstream of the gate. It is found for ordinary operating conditions that the curvature of the layers of the stream starts at a location upstream from the gate where the static pressure has not yet fallen below about 80% to 90% of the upstream static head and that the curvature of these layers flowing downstream from the gate substantially ends when, at the base wall surface or bottom of the channel, the static pressure has fallen to about of the upstream static pressure.

When the gate is in a position greatly restricting the flow, the isobar for 10% of the upstream static head may intersect the base wall surface of the downstream flow channel at a relatively small distance downstream from the flow control edge of the gate, that is, usually the lower edge at the upstream face of the gate. For example, with an opening of the gate at 0.4 of its full opening height this 10% isobar may intersect the base wall surface at a point which is distant downstream from the plane of the upstream face of the gate equal to about /3 of the full height of the channel, that is, of the full opening of the gate. With the gate in the position of 0.6 open the isobar of 10% of the upstream static pressure intersects the base wall at a distance downstream from the upstream face of the gate equal to about /2 of the full height of the gate opening. With greater amounts of opening of the gate the intersection of the 10% isobar with the base wall occurs still further downstream from the upstream face of the gate but with such further opening and greater area of flow the curvatures of the layers become very much reduced and the effect of the excessive gradient of static pressure added to the normal gradient of static pressure in the manner above referred to begins to be negligible.

Similar relations of gate opening to distance from the gate are found to apply which determine locations upstream of the gate which are favorable for avoiding turbulence, cavitation and jet action, although the total pressure in the hydraulic fluid is greater than in the hydraulic fluid downstream of the gate.

The invention principally will be described in the as pect thereof relating to utilizing the favorable conditions downstream from the gate. In accordance with this aspect of the invention, in order to secure the hydraulic eondition in which the formation of the jets projecting into the grooves is prevented or greatly reduced, the grooves and the supporting slideways or rollways disposed therein are positioned preferably, for this downstream location, adjacent the point of intersection with the base wall of the 10% isobar which is developed for the given amount of opening of the gate. This selection may be made within close limits when, in practical operation of the hydraulic plant, the gate is normally to be held in a position determining a fairly definite amount of opening. Where the amount of opening may be required to be varied, the position of the grooves may be determined within a range which is indicated by the distance between the intersections with the base wall of the respective 10% isobars for the two extreme operating positions of the gate which would generally be used. In general in such hydraulic plants these grooves and the gate supporting slideways or rollways therein will be positioned downstream with respect to the gate not substantially less than a distance from the upstream face of the gate equal to A of the height of the full opening of the gate.

In general the upstream face of the gate, and particularly the bottom or flow control edge of the gate, will be disposed upstream with respect to the position of the grooves in the lateral walls of the tunnel or channel in which the supporting means, specifically the slideways or rollways, are usually disposed. As will be more clearly understood from the description of the invention taken in connection with the drawings, the gate may have different forms while carrying out this general function.

It will be understood, although ordinarily the determinations will be based on the height of the full opening of the gate substantially equal to the height of the flow channel upstream of the gate, whether this channel be an open channel or a closed conduit or tunnel, that in some cases, especially where long channels upstream of the gate are utilized, a loss of head develops in this channel and it is necessary to take this loss into account in determining the position of the grooves in the lateral walls of the channel downstream with respect to the gate. Since this loss of head in the upstream channel limits the discharge through the gate opening, it may occur that a maximum discharge is reached when the gate, is, for example, half open and consequently there no longer is obtained any effect of regulating the flow in the upper half of the movement of the gate. The disposition of the grooves in such case may be made on the basis, for

example, of of the height of the channel. In the case of short upstream channels, however, particularly if the gate must remain for a long time in a partially open position in the range between /2 opening and full opening,

" it may be necessary to make the distance equal to at formly to the rollway a thrust not uniformly applied.

In the gate structure to which the invention relates, however, the force due to the hydraulic pressure on the gate may be distributed substantially uniformly to the roller structure. This result is made possible because a suitable connecting structure may be provided in the space between the gate and the roller structure which develops due to the spaced relation (upstream or downstream) of the gate with respect to the grooves in which the rollers are disposed. Moreover, to meet the well known condition that the center of pressure of the water on the gate is disposed below the center of the height of the gate, in order to provide the desired uniform distribution of the force, in accordance with the invention the rollers or the sets of rollers along each rollway are arranged symmetrically above and below the horizontal plane through the center of pressure of the Water on the gate. The rollers as a group, therefore, will be located somewhat towards the lower or control edge of the gate.

While the position of the center of pressure of the gate disposed in an open channel varies with the amount of opening of the gate, a substantially symmetrical disposition of the rollers in the direction along the rollways and with respect to the center of pressure on the gate is utilized for the fully closed position of the gate. This disposition of the rollers will develop for other positions of the gate a satisfactory distribution of the pressure.

In a closed conduit or tunnel, the construction may be such that the position of the center of pressure does not vary with the amount of opening of the gate and corresponds to the fully closed position as will be more clearly understood from the description of the drawings to follow.

This feature of the distribution of the rolls along the rollways is applicable with equal advantage to the second aspect of the invention in which the gate is disposed downstream with respect to its supporting structure and the grooves, as hereinafter further described.

The invention in both aspects will be understood in greater detail by reference to the description which follows taken in connection with the drawings in which FIG. 1 relates to the first aspect and is a diagrammatic longitudinal section of a flow channel provided with a conventional fiat gate partially open;

FIG. 2 is a similar diagrammatic longitudinal section with the gate in a position of increased opening;

FIG. 3 shows a curve giving as abscissae the distance downstream from the gate to the grooves for varying amounts of opening of the gate plotted as ordinates;

FIG. 4 is a diagrammatic longitudinal vertical section of a closed channel or pressure conduit or tunnel and a gate disposed therein embodying the first aspect of the invention;

'FIG. 4a is a partial perspective view of the. gate of FIG. 4;

FIG. 5 is a horizontal section on line 5-5 of FIG. 4;

FIG. 6 is a diagrammatic longitudinal vertical section of a closed channel or pressure conduit or tunnel and a gate of modified form disposed therein embodying the first aspect of the invention;

FIG. 7 is a horizontal section on line 7--7 of FIG. 6;

FIGS. 8 and 9, respectively corresponding to FIGS. 1 and 7, show a diagrammatic longitudinal section of a how channel and a horizontal section in accordance with the second aspect of the invention.

In FIGS. 1 and 2 the flow of the hydraulic fluid is efiected as shown by the arrows horizontally from right to left through a channel provided by lateral walls 3 and base walls 5, the gate 7 in this simple construction being disposed with its planar extent transverse to the direction of flow and restricting the flow of the water through the orifice or opening formed below the bottom edge 9 of the gate 7. The flow occurs about the upstream corner 11 of the bottom edge with concomitant contraction of the flow as referred to. FIGS. 1 and 2 respectively show the gate in the two positions in which it is .4 open and .6 open, full opening being the height of the water in the upstream channel. T he flow lines 13 represent the imaginary layers of the water which become curved in the region adjacent the upstream face of the gate, changing to this curvature from the generally horizontal direction in the upstream region, and then reversely curving as the water flows about the corner 11 of the gate, this reverse curvature again flattening until the layers flow downstream from the gate generally parallel to the base wall 5. In the regions of curvature the gradient of velocity and the concomitant developing of the excessive gradient of static pressure occur as above mentioned.

In FIGS. 1 and 2 in dotted lines are shown the isobars 90% and 80% of the upstream static head in the region immediately upstream of the gate, and the isobar 50% of the upstream static head generally in the plane of the upstream face of the gate 7 and the isobar of this upstream static head in the region extending from the upstream face of the gate to the point where this 10% isobar intersects the "bottom wall of the channel. It will be noted in the region where the 10% isobar intersects the bottom wall of the channel that the layers of the water how have become almost horizontal so that the vertical gradient of pressure now has been lost.

The grooves for the rollways or slideways for supporting the gate for vertical movement preferably would be disposed, for the two amounts of opening of the gate as shown in FIGS. 1 and 2, substantially at these points of intersection of the 10%isobars. For practical construction these grooves may be positioned in planes selected as indicated by the vertical dotted lines 21, 23, 25 which are disposed at distances equal to respectively A, /3

and /2 of the height of the opening of the gate, this distance being measured downstream from the upstream :face 8 of the gate. These distances may be determined approximately from the curve D as shown in FIG. 3 in which the ordinates represent the decimal parts of the full opening of the valve and the abscissae represent dis tances downstream which are equal to decimal fractions of the height of the full opening of the gate. In general, it will be found that the grooves should be disposed in a plane transverse to the direction of hydraulic flow which is positioned downstream from the upstream face of the gate not substantially less than A of the height of the hull opening of the gate. Preferably for ordinary conditions of operation with the gate open, for example, between 0.4 and 0.6 of its full opening, the grooves will be disposed in a plane distant downstream from the upstream face of the gate not substantially less than /3 of the full opening of the gate.

It will be understood, in order to carry out-the functions of the gate as above described in accordance with the invention, that a suitable mechanical construction of the gate must be provided in order to dispose the upstream face of the gate and particularly the upstream lower edge thereof, at the desired distance upstream with respect to the position of the grooves in the lateral walls of the flow channel, in which grooves the rollways or slideways are positioned. The gate also must be designed so that it will shut oif the how in the channel and, therefore, must cooperate with the bottom or base wall of the channel in closing relation thereto. Two constructions capable of carrying out the functions of the gate of the invention are disclosed in FIGS. 4 and 5 and in FIGS. 6 and 7.

FlGS. 4 and 5 show an embodiment of a carriage gate 30 designed (for restricting the flow through and for shutting off the closed pressure conduit or tunnel 31. For support of the gate rollways 33 are mounted on the structure forming the lateral walls 3 of the tunnel, these rollway-s being disposed adjacent the downstream transverse face 35 of the grooves 37 formed respectively in these lateral walls. The gate provides a structure 39 which substantiallycomprises a plurality of horizontal beams 41 extending into the grooves 37 connected by struts 42 at their ends carrying the rollers 43 which roll on the rollways 33. At the other transverse Wall 45 of the groove a second trackway 47 is provided upon which a steady arm 49 may bear for guiding the gate in its vertical movement when it is not under the hydraulic pressure of water at its upstream face.

Disposed upstream with respect to the structure 39 which comprises the beams 41 the gate is provided with a wall 51 of arcuate form extending from the portion of the beam structure adjacent one lateral wall 3 to the portion of this structure adjacent the opposite lateral wall 3. The end portions of the arcuate wall 51 may be connected in water-tight relation to the beam structure and to walls 53 which extend parallel to the Walls 3 upstream from the beam structure 39 to theposition of sealing members 55 carried by the walls 3 which are engaged by a sealing gasket 57 carried by walls 53. The arcu-ate Wall 51 and the walls 53 may be braced with respect to each other by intermediate webs 5 9 of suitable form.

It will be understood that the hydraulic pressure which is brought upon the arcuate wall 51 of the gate 30 at the upstream face of this wall is transmitted through the arcuate wall and the web structure and through the beam structure 39 to the rollways 33 so that the total hydraulic pressure exerted upon the gate is transmitted through these rollways to the portions of the lateral walls at the transverse Walls 35 of the grooves. The pressure thus exerted upon the arcuate wall 51 may be considered to be exerted at a center of pressure which is at a level of half of the height of the wall 51 as shown in FIG. 4 because the wetted surface is always that of the maximum height of the gate in all positions, due to the location of the sealing gasket 107 carried at the upper edge of the gate and movable therewith.

It will be noted in FIGS. 4, 4a and that the bottom edge 60 of the gate extends transversely across the channel and is disposed upstream with respect to the grooves 37. After the contraction of the water flow which is effected by this lower edge 60 of the gate, the flow becomes changed from the curvilinear form again to the generally horizontally extending flow as described in connection with FIGS. 1 and 2 by the time that the flow reaches the plane of the grooves 37, thereby to carry out the purpose of the invention which has been described above.

The arcuate form of the wall 51 may be modified from the circular are shown in FIG. 5 to some other arcuate form which will secure the disposition of the bottom edge 69 sufliciently upstream with respect to the grooves 37 so that the condition is provided that the grooves are disposed in the region where the isobar intersects the surface of the base wall 5 of the tunnel, or that these grooves are disposed downstream with respect to the bottom edge 60 of the gate so that the distance between the grooves and this bottom edge is not substantially less than A of the height of the opening of the gate.

It also will be noted in FIGS. 4, 4a and 5 that the gate structure within the arc of the wall 51 is braced by ribs 52 extending along the arcuate extent of the wall 51 and connecting to the beam structure 39, 41. There thus is provided an open space, as may be seen in FIGS. 40, above the contracted portion of the stream which provides for movement of air between this open space above the contracted portion of the stream, and the downstream tunnel 67 so as to avoid cavitation. The space beneath the bottom end web 59 and the lowermost rib 58 of the gate structure and downstream with respect to the edge 60 may be divided, as shown in FIGS. 4a and 5, by vertical webs 44 to divide the eddies and to reinforce the structure providing the lower control edge 69.

The shaft 65 may be of suitable dimension to provide for lowering and raising the gate 30. Conventional means not shown may be used for effecting this raising and lowering of the gate.

In the embodiments of FIGS. 6 and 7 the gate is constituted by an apron 71 of hollow structure formed with planar walls 73 braced by inner webs 75. This apron may be of relatively small thickness between the walls 73, the gate structure providing breast members 77 which extend transversely of the plane of the apron toward the rollways 79 carried by the lateral walls 3 at the transverse walls 81 of the grooves 83. These walls 81 of the grooves 83 in the embodiment of FIGS. 6 and 7 are disposed in inclined relation to the faces of the lateral walls 3 and the extent of the breast members 77 in the direction in which the thrust is transmitted from the apron to the rollways 79 is perpendicular to the respective walls 81 and to the rollways 79. The breast members 77 at the ends thereof adjacent the rollways 79 are provided with brackets 85 which are in bearing relation to slideways 87 carried at the other transverse walls 89 of the grooves 83 for guiding the gate in its movement when the pressure of the hydraulic flow is not exerted on the gate.

Breast members 77 are constructed in the embodiment of FIGS. 6 and 7 with webs 91 generally in the horizontal plane and extending between vertical flanges 93 and 95 which are of such form cooperating with the webs 91 that the breast members have a wide base engagement with the apron 71 both in the horizontal direction and in the vertical direction. The portion 97 of the breast member structure adjacent the rollways 79 may be continuous in the vertical direction between the three breast members shown one above the other in FIG. 6 and this continuous portion as a beam carries the rollers 99 suitably supported thereon for distributing the pressure of the thrust through these rollers on the rollway 79. It will be understood that in this embodiment also the distribution of rollers 99 along the beam 97 and along rollway 79 may be such as to secure substantially uniform distribution of the pressure by virtue of the position of the rollers with respect to the center of pressure of the gate.

It will be understood further that the arrangement of FIGS. 6 and 7 has the advantage of transmitting the thrust from the gate through the breast members to the structure of the lateral walls 3 in directions which are not parallel to the direction of flow but at an angle thereto, so that an obtuse angle is formed at the outer corner of the groove and the mass of the wall structure is more effective to resist the thrust and other forces.

As shown in FIG. 7 the vertical lateral edges of the apron 71 may carry a gasket or other sealing means 103 bearing on the plates -105 carried by the walls 3 for sealing against passage of the water around the vertical edges of the apron 71 while providing for the requisite vertical movement of the gate. In FIGS. 4 and 6 also a gasket or other suitable means 107 is provided for securing tightness between the upstream face of the shaft 65 and the gate for various positions of the gate.

FIG. 8 shows a diagrammatic longitudinal section similar to FIG. 1 but, as indicated at 110, with grooves and the structure supported therein disposed upstream with respect to the gate 7. This disposition of the grooves is shown for a gate opening of .4 corresponding to that of FIG. 1, the grooves being spaced upstream from the upstream face 8 of the gate 7 a distance of about /3 of the height of the full gate opening. This spacing corresponds generally to that in FIG. 1 in which at the line 23 the 10% isobar intersects the bottom wall 5 of the channel. In FIG. 8, however, the line 110 indicates approximately the position at which in the oncoming water layers curvature from the horizontal is started, that is, the position at which turbulence, cavitation and jet action have not yet occurred in the grooves to any degree detrimental to the said grooves and the gate supporting structure.

In this second aspect if the gate opening were .6 corresponding to that of FIG. 2, the grooves would be disposed further upstream, for example, at a distance from the gate equal to about /2 of the height of the full gate opening in order that the grooves and the rollway structure would not be subject to substantial turbulence and cavitation.

In the horizontal section of FIG. 9 at gate structure is shown with planar walls 1'15 spaced apart and braced by connecting webs 117. This gate is supported for movement on rollways .119 disposed at the downstream walls 121 of the grooves 123 formed in lateral walls 3 of the channel, rolls .124 rolling on the rollways 119 and being carried by vertically extending hollow struts 125 disposed parallel to and within the vertical grooves 123. Brackets 1 29 are carried by struts 125 and bear in sliding relation on slideways 131 carried on the upstream walls 133 of groove 123 to steady the structure in its movement upwardly and downwardly.

Connecting between the gate and the struts hollow tie members 135 are disposed parallel to the vertical lateral walls 3. The tie members 135 are formed with parallel walls 137 spaced and held together by webs 139. The tie members serve to transmit through the struts 125 to the rollways 119 the forces brought upon the gate by the water pressure and at the same time to hold the gate in rigid relation to both struts 125. A plurality of cross frame members 140 one above the other in the vertical plane and each connected to the two tie members 135 are used in FIG. 9 to complete a rigid structure.

Sealing plates 141 carried by Walls 3 and gaskets 143 carried by the gate structure cooperate to seal against leakage past the gate while providing for the vertical movement of the gate.

In the first aspect of the invention the gate is made tight to the walls in locations upstream from the grooves and all of the structure downstream of the upstream face of the gate, and particularly the grooves and the rollway structure and the roller supports, as well as the access shaft, is removed from the zone of pressure upstream of the gate. That is to say, none of these parts are submerged. Under some conditions, however, it may be advantageous as to construction and space available to dispose the grooves and the rollway and roller structure upstream of the gate and submerged in the water flowing to the gate, even though this structure is subjected to the full hydraulic pressure and the access pit is occupied more or less by the water when the valve is closed or partially closed.

Another advantage is secured by the arrangement of the second aspect since the structure, such the tie members 135, FIG. 9, connecting the gate to the rollway structure is under tension as compared with the struts or breast members 77 of FIGS. 6 and 7 which must resist compressive force and buckling and thus are required to be of heavier construction.

In both aspects of the invention the distance between the flo-w'control edge of the gate and the members which carry the rollers engaging the rollways is considerable. The strut or breast member structure and that providing the tie members spanning this distance in the respective aspects may be designed, however, so that the construction will not be substantially heavier than that of conventional gates While securing a strong structure.

The invention in its broad concept contemplates disposition of the grooves and the rollway structure in relation to the gate in accordance with either aspect of the invention as described to secure the avoidance of the undesirable action of the water and the pressure thereof on the grooves, the rollways and slideways and the structure supporting the gate on these roll'ways and slideways. Various modifications may be made to suit different conditions without departing from the essential concept as described and as defined in the accompanying claims.

In these claims the term channel is intended to be generic to include both an open channel or canal in which the Water flows, usually generally horizontally, without a confining wall at the top of the lateral walls and also to include a closed conduit or tunnel capable of confining the water under pressure.

I claim:

1. In a hydraulic plant providing a flow channel composed of a base wall and spaced lateral walls, a gate having its plane of surface transverse to the direction of said how along said walls, said gate including an apron having lateral edge portions respectively disposed adjacent said lateral walls, and a structure for supporting said apron and having lateral side portions adjacent said walls, means supporting said structure for movement thereof along said lateral Walls transversely of said direction of flow, including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with said lateral side portions of said structure, said lateral side portions of said structure being located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the flow of hydraulic fluid defined by said walls and containing such fluid, said apron being provided at its lower portion with a flow control edge exending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral Walls defining a flow orifice variable upon said movement of said gate, and the whole of said flow control edge and therefore all of said flow orifice being substantially spaced from all of said grooves in a direction parallel to said flow of the hydraulic fluid in said channel.

2. In a hydraulic plant providing a flow channel composed of a base wall and spaced lateral walls, a gate having its plant of surface transverse to the direction of said flow along said walls, said gate including an apron hav- .ing lateral edge portions respectively disposed adjacent 10 said lateral walls, and a structure for supporting said apron and having lateral side portions adjacent said walls, means supporting said structure for movement thereof along said lateral walls transversely of said direction of flow, including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with said lateral side portions of said structure,

said lateral side portions of said structure being located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the flow of hydraulic fluid defined by said walls and containing such fluid, said apron being provided at its lower portion with a flow control edge extending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral walls defining a flow orifice variable upon said movement of said gate, and the whole of said fiow control edge and therefore all of said flow orifice being substantially spaced upstream in said channel with respect to all of said grooves.

3. In a hydraulic plant providing a flow channel composed of a base wall and spaced lateral Walls, a gate having its plane of surface transverse to the direction of said flow along said Walls, said gate including an apron having lateral edge portions respectively disposed adjacent said lateral Walls, and a structure for supporting said apron and having lateral side portions adjacent said walls, means supporting said structure for movement thereof along said lateral walls transversely of said direction of flow including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with said lateral side portions. of said structure, said lateral side portions of said structure be ing located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the fiow of hydraulic fluid defined by said walls and containing such fluid, said apron being provided at its lower portion with a flow control edge extending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral walls defining a flow orifice variable upon said movement of said gate, and the whole of said flow control edge and therefore all of said flow orifice being substantially spaced downstream in said channel with respect to all of said grooves.

4. In a hydraulic plant as defined in claim 1 in which said flow control edge extends substantially between said lateral walls, and in which said gate comprises means including said gate and said structure extending as a whole in a direction parallel to said fiuid flow for a substantial distance and maintaining said flow control edge substantially spaced from all of said grooves throughout said extent thereof.

5. In a hydraulic plant providing a flow channel, the combination as defined in claim 4 in which said flow control edge is rectilinear.

6. In a hydraulic plant providing a flow channel composed of a base wall and spaced lateral walls, a gate having its plane of surface generally at right angles to the direction of flow along said channel, said gate having lateral edge portions respectively disposed adjacent said lateral walls, means for supporting said gate for movement thereof transversely of said direction of how with said edge portions moving along said lateral walls at right angles to said flow and including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with said gate lateral edge portions, said gate lateral edge portions being located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the fiow of hydraulic fluid defined by said walls and containing such fluid, said gate being provided at its lower portion with a flow control edge extending substantially between said lateral Walls and defining with said base wall and said lateral walls a flow orifice variable upon operation of said gate from and to the closed position in which said flow control edge engages said base wall, the whole of said flow control edge and therefore all of said flow orifice being disposed in substantially spaced relation with respect to all of said grooves in a direction along said flow of the hydraulic fluid in said channel.

7. In a hydraulic plant as defined in claim 6 in which the outline of the section of said gate in a plane parallel to said base wall and extending substantially between said lateral edge portions is arcuate with the control portion of such arcuate section substantially spaced from said grooves, and in which said flow control edge extends across said base wall below said arcuate gate section and in generally tangential relation to Such central portion of such section.

8. In a hydralic plant as defined in claim 1, in which said gate apron is generally planar and as a whole, is spaced in a direction along said flow with respect to said grooves, and extends substantially between said lateral walls transversely of said direction of flow along said channel, said flow control edge being provided at the bottom edge of said planar apron, and said gate structure comprising supporting members disposed between said apron and the grooves provided on said lateral walls in force transmitting relation therebetween to transmit the force of the flow on said apron to said lateral walls and to support said apron in said spaced relation with respect to said grooves '9. In a hydraulic plant as defined in claim 8 in which said planar apron is disposed upstream so that said supporting members are in thrust transmitting relation between said apron and said grooves of said lateral walls, and in which said supporting members are disposed with the dimension thereof along the respective lines of thrust extending in oppositely directed angular relation to said lateral walls and to the plane of said apron.

10. In a hydraulic plant as defined in claim 9 in which said grooves provided in said lateral walls comprise trackways disposed in planes respectively perpendicular to said line of thrust of said supporting members and in angular relation to each other, the portions of said supporting members adjacent to said trackways comprising the lateral portions of said structure, and means carried by said supporting member portions and engaging said trackways to provide for movement of said supporting members and said apron supported thereby along said trackways.

11. In a hydraulic plant as defined in claim 1 in which said gate apron extends substantially between said lateral walls of said channel transversely of said flow and is carried by said gate structure so that it is disposed as a whole in substantially spaced relation to said lateral wall grooves, and said gate apron being composed of a continuous wall capable of holding the hydraulic fluid against flow through said frame, said flow control edge of said gate being disposed on the bottom edge of said continuous wall and extending substantially between said lateral walls of said channel.

12. In a hydraulic plant providing a flow channel composed of a .base wall and spaced lateral walls, a gate having its plane of surface transverse to the direction of said flow along said walls, said gate including an apron having lateral edge portions respectively disposed adjacent said lateral walls, and a structure for supporting said apron, means supporting said structure for movement thereof along said lateral walls transversely of said direction of flow, including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with the lateral portions of said structure associated therewith and extending into the flow of hydraulic fluid between said walls, said apron being provided at its lower portion with a flow control edge extending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral walls defining a flow orifice variable upon said movement of said gate, and the whole of said flow control edge and therefore all of said flow orifice being substantially spaced from all of said grooves in a direction parallel to said flow of the hydraulic fluid in said channel and at a distance not substantially less than A of the height of the full opening of said gate.

13. In a hydraulic plant providing a flow channel composed :of a base wall and spaced lateral walls, a gate having its plane of surface transverse to the direction of said flow along said walls, said gate including an apron having lateral edge portions respectively disposed adjacent said lateral walls, and a structure for supporting said apron and having lateral side portions adjacent said walls, means supporting said structure for movement thereof along said lateral walls transversely of said direction of flow, including a plurality of grooves of substantial width formed in said lateral Walls in adjacent substantial parallelism with said lateral side portions of said structure, said lateral side portions of said structure being located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the flow of hydraulic fluid defined by said walls and containing such fluid, said apron being provided at its lower portion with a flow control edge extending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral walls defining a flow orifice variable upon said movement of said gate and the whole of said flow control edge and therefore all of said flow orifice being substantially spaced from all of said grooves in a direction parallel to said flow of the hydraulic fluid in said channel and at a distance approximating the distance from the upstream plane of surface of said gate to the point at which the isobar of 10% of the upstream static pressure extending from such upstream plane of Surface intersects with the surface of said base wall.

14. In a hydraulic plant providing a flow channel composed of a base wall and spaced lateral walls, a gate having its plane of surface transverse to the direction of said flow along said walls, said gate including an apron having lateral edge portions respectively disposed adjacent said lateral walls, and a structure for supporting said apron and having lateral side portions adjacent said walls, means supporting said structure for movement thereof along said lateral walls transversely of said direction of flow, including a plurality of grooves of substantial width formed in said lateral walls in adjacent substantial parallelism with said lateral side portions of said structure, said lateral side portions of said structure being located in said grooves for sliding movement therein, and said grooves, at least in part, being in open communication with the sides of the flow of hydraulic fluid defined by said walls and containing such fluid, said apron being provided at its lower portion with a flow control edge extending transversely of said lateral walls and disposed toward said base wall, said flow control edge, said base wall and said lateral walls defining ta flow orifice variable upon said movement of said gate, and the whole of said flow control edge and therefore all of said flow orifice being substantially spaced from all of said grooves in a direction parallel to said flow of the hydraulic fluid in said channel to dispose said lateral wall grooves adjacent a location of substantially no pressure gradient producing curvature of the flowing fluid developing flow transversely of said channel.

15. Ina hydraulic plant as defined in claim 1 in which said gate apron is disposed downstream with respect to said lateral wall grooves, and in which said gate structure includes tie members operatively connecting said gate apron with said lateral portions thereof and subjected to tension transmitted thereto from said gate apron under the hydraulic pressure at the upstream plane of surface of the latter.

16. In a hydraulic plant as defined in claim 1 including 13 liquid sealing means provided on said lateral edge portions of said gate apron and respectively engaging said lateral walls in leak resisting relation While providing for said movement of said .gate transversely of said direction of flow.

17. In a hydraulic plant as defined in claim 1 including a closing wall disposed in opposed relation to said base wall and cooperating with the latter and said lateral walls to provide a pressure confining conduit for the hydraulic fluid, and including liquid sealing means providing a leak resisting relation between said gate and said closing and lateral walls while providing for said movement of said gate transversely of said direction of flow.

18. In a hydraulic plant as defined in claim 1 in which the major portion, at least, of the upstream face of said gate is spaced from said lateral wall grooves in the direction of said fluid flow, and in which said flow control edge is provided at the bottom of such upstream face, both said bottom of such upstream face and said flow all of said grooves in the direction of said fluid flow.

the central portion of said convex.

References Cited in the file of this patent UNITED STATES PATENTS 1,562,113 Meyer Nov. 17, 1925 2,006,252 Zimmerman June 25, 1935 2,035,833 Peilert Mar. 31, 1936 FOREIGN PATENTS 101,370 Austria Oct. 26', 1925 618,135 France Dec. 10, 1926 143,934 Switzerland Mar. 2, 1931 620,265 Great Britain of 1949 756,467 Ger-many of 1951 D19,630 Germany Sept. 6, 1956 196,803 Austria Mar. 25, 1958 

1. IN A HYDRAULIC PLANT PROVIDING A FLOW CHANNEL COMPOSED OF A BASE WALL AND SPACED LATERAL WALLS, A GATE HAVING ITS PLANE OF SURFACE TRANSVERSE TO THE DIRECTION OF SAID LATERAL EDGE PORTIONS RESPECTIVELY DISPOSED ADJACENT SAID LATERAL WALLS, AND A STRUCTURE FOR SUPPORTING SAID APRON AND HAVING LATERAL SIDE PORTIONS ADJACENT SAID WALLS, MEANS SUPPORTING SAID STRUCTURE FOR MOVEMENT THEREOF ALONG SAID LATERAL WALLS TRANSVERSELY OF SAID DIRECTION OF FLOW, INCLUDING A PLURALITY OF GROOVES OF SUBSTANTIAL WIDTH FORMED IN SAID LATERAL WALLS IN ADJACENT SUBSTANTIAL PARALLELISM WITH SAID LATERAL SIDE PORTIONS OF SAID STRUCTURE, SAID LATERAL SIDE PORTIONS OF SAID STRUCTURE BEING LOCATED IN SAID GROOVES FOR SLIDING MOVEMENT THEREIN, AND SAID GROOVES, AT LEAST IN PART, BEING IN OPEN COMMUNICATION WITH THE SIDES OF THE FLOW OF HYDRAULIC FLUID DEFINED BY SAID WALLS AND CONTAINING SUCH FLUID, SAID APRON BEING PROVIDED AT ITS LOWER PORTION WITH A FLOW CONTROL EDGE EXTENDING TRANSVERSELY OF SAID LATERAL WALLS AND DISPOSED TOWARD SAID BASE WALL, SAID FLOW CONTROL EDGE, SAID BASE WALL AND SAID LATERAL WALLS DEFINING A FLOW ORIFICE VARIABLE UPON SAID MOVEMENT OF SAID GATE, AND THE WHOLE OF SAID FLOW CONTROL EDGE AND THEREFORE ALL OF SAID FLOW ORIFICE BEING SUBSTANTIALLY SPACED FROM ALL OF SAID GROOVES IN A DIRECTION PARALLEL TO SAID FLOW OF THE HYDRAULIC FLUID IN SAID CHANNEL. 